In a second aspect, the invention also relates to a method for producing slivers with natural fibers. In a third aspect, the invention also relates to a use of a device according to the first aspect or a method according to the second aspect for producing flax slivers.

PRI OR ART Flax is a plant with a woody stem of approx. 800 to 1200 mm long, which is made up of fiber strands in the longitudinal direction of the stem, and a woody fraction, which is called "shives". The release of the fibers and the separation of the woody fraction is called "decortication". Flax decortication is traditionally carried out on a scutching line. The flax is fed in in a continuous layer with a thickness that is as constant as possible, with the stalks at right angles to the feed-through direction. First, the woody fraction of the stems is broken by breaking. Then, in a scutching turbine, the shives are beaten or rubbed away from the fibers.

At the exit of the scutching line, the long scutched flax fibers (600-1200 mm) lie transversely over successive outfeed transport belts. To this day, these fibers are brought to a flat track and rolled in a winder into rolls with a diameter of 600 mm, a width of 600 mm and a weight of approx. 100 kg, in which all the scutched fibers are oriented parallel to the axis line of the roll.

These rolls are then delivered to a hackling mill, where the fibers are combed out, divided into packs and then placed on top of each other longitudinally, creating a continuous sliver of approx. 35 g/m. The sliver formation is slow and in several steps. These slivers are then processed in the spinning preparation to form finer and uniform slivers, from which a yarn can be spun. The hackling, spinning preparation and spinning mainly takes place in low-wage countries, usually with outdated machines, with very low efficiencies.

Known devices are disclosed in SU 825 685 and GB 2 005 321.

There is a need for an improved method in which a sliver is delivered directly after the scuttle turbine, without the use of a hackling machine, and in which the produced sliver can be further processed in the spinning preparation.

The present invention aims to find a solution for at least some of the above problems.

SUMMARY OF THE I NVENTI ON

In a first aspect, the present invention relates to a device according to claim 6.

The main advantage of a device according to the present invention is that the supply direction A and the sliver forming direction B form an angle Q of at least 20° and at most 180° and that the conveyor belt of the sliver forming line intersects a side edge of the transport device of the supply line between the first end and the second end of the transport device of the supply line, said side edge extending along the supply direction A, whereby the natural fibers are pulled at an angle to the supply direction A from the layer of natural fibers on the supply line onto the sliver forming line and are automatically placed on top of each other in a longitudinal direction to form a sliver. A hackling machine in its traditional and outdated form, in which a sliver can only be formed after hackling and in several steps, is now superfluous for this purpose and a sliver can be formed with high efficiency immediately after scutching. Afterwards, the slivers can be further combed with modern machines. An additional advantage is that the natural fibers can be fed directly from a scutching machine to a device according to the present invention, so that it is unnecessary to roll up the natural fibers. The invention can also be used to transform already rolled up scutched natural fibers into slivers after unrolling.

Preferred embodiments of the device are set out in claims 7-14.

A particular preferred form of the invention relates to a device according to claim 7. In this preferred form, the conveyor belt of the sliver forming line comprises combs for pulling out and entraining the natural fibers from the layer of natural fibers on the supply line to form a sliver. By means of the combs, the natural fibers are guaranteed to be pulled from the supply line onto the sliver forming line. An additional advantage is that the natural fibers are at least partially combed at the same time.

In a second aspect, the present invention relates to a method according to claim 1.

This method has the advantage, among other things, that a sliver of natural fibers can be formed immediately after scutching, without the natural fibers first having to be hackled in a hackling machine, in its traditional and outdated form, and it only then being possible for them to be formed into a sliver in several steps. An additional advantage of this method is that it is many times more efficient than a traditional method in which the natural fibers are rolled up after scutching, after which they have to be unrolled and hackled again before a sliver can be formed. The method can also be used to transform already rolled up scutched natural fibers into slivers after unrolling.

Preferred forms of the method are described in dependent claims 2-5.

In a third aspect, the present invention relates to a use according to claim 15.

This use results in an advantageous formation of a sliver from flax or hemp, because sliver formation can be carried out in an efficient manner immediately after scutching. This is particularly advantageous because much flax and hemp is grown in northern France, Belgium and the Netherlands, but is hackled and spun in low-wage countries. Due to the efficient formation of a sliver from flax or hemp, at least part of the processing of flax or hemp can be kept local, thus avoiding or reducing transport costs.

BRI EF DESCRI PTI ON OF THE FI GURES

Figure 1 A, Figure 1 B, Figure 1 C and Figure 1 D show schematic plan views of mutual positions of the conveyor belts of the supply line and the sliver forming line according to various embodiments of the present invention. Figure 2 shows a side view of a device according to an embodiment of the present invention.

Figure 3 shows a front view of a device according to an embodiment of the present invention.

Figure 4 shows a plan view of a device according to an embodiment of the present invention.

Figure 5 shows a perspective view of a device according to an embodiment of the present invention.

DETAI LED DESCRI PTI ON

Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meaning as commonly understood by a person skilled in the art to which the invention pertains. For a better understanding of the description of the invention, the following terms are explained explicitly.

In this document, "a" and "the" refer to both the singular and the plural, unless the context presupposes otherwise. For example, "a segment" means one or more segments.

The terms "comprise", "comprising", "consist of", "consisting of", "provided with", "include", "including", "contain", "containing", are synonyms and are inclusive or open terms that indicate the presence of what follows, and which do not exclude or prevent the presence of other components, characteristics, elements, members, steps, as known from or disclosed in the prior art.

Quoting numerical intervals by endpoints comprises all integers, fractions and/or real numbers between the endpoints, these endpoints included.

The term "natural fibres" is defined as fibers of natural origin, more preferably vegetable origin. Examples of natural fibers include flax, hemp, jute, manila hemp, sisal, ramie, nettle, raffia, or ficus. In a first aspect, the invention relates to a device for producing slivers with natural fibers, such as flax sliver.

According to a preferred embodiment, the device comprises a supply line for a layer of natural fibers and a sliver forming line for forming a sliver from the natural fibers in the layer of natural fibers on the supply line.

The supply line comprises a transport device. The transport device of the supply line extends from a first end along a supply direction A to a second end. The supply line is configured to move the layer of natural fibers in the supply direction A. The transport device of the supply line comprises a surface, a bearing surface, which is configured to at least partially support the natural fibers in the layer of natural fibers, with the natural fibers oriented in a direction transverse to the supply direction A.

The sliver forming line comprises a conveyor belt. The conveyor belt of the sliver forming line extends from a first end along a sliver forming direction B to a second end. The sliver forming line is configured to entrain natural fibers from the layer of natural fibers on the supply line in the sliver forming direction B. Preferably, the speed of entrainment is higher than the speed of supply. The conveyor belt of the sliver forming line is suitable for fully supporting the natural fibers, wherein the natural fibers are oriented in a direction parallel to the sliver forming direction B.

The conveyor belt of the sliver forming line intersects a side edge of the transport device of the supply line between the first end and the second end of the transport device of the supply line. Said side edge extends along the supply direction A.

The supply direction A and the sliver forming direction B form an angle Q of at least 20° and at most 180°. The angle Q is determined as the smallest angle between the positive sense of the supply direction A and the positive sense of the sliver forming direction B. This means that at an angle Q of 180° the directions A and B are opposite directions.

Natural fibers are provided in a layer with a thickness that is as uniform as possible on the transport device of the supply line, the layer of natural fibers being partially supported by the transport device of the supply line. An overhanging part of the natural fibers in the layer of natural fibers is positioned on the side of the sliver forming line. Because the conveyor belt of the sliver forming line intersects a side edge of the transport device of the supply line between the first end and the second end of the transport device of the supply line, the overhanging part of the natural fibers at the level of the conveyor belt of the sliver forming line will be pulled out of the layer of natural fibers on the supply line by the conveyor belt of the sliver forming line and entrained on the conveyor belt of the sliver forming line. Because the natural fibers on the conveyor belt of the sliver forming line move in a different direction and optionally faster than on the transport device of the supply line and because initially only the overhanging part of the natural fibers are entrained by the conveyor belt of the sliver forming line, the natural fibers are entrained in a direction parallel to the sliver forming direction B and superimposed in a longitudinal direction of the natural fibers, whereby a sliver is formed.

A device according to the present invention is advantageous in that a hackling machine in its traditional and outdated form, in which a sliver can only be formed after hackling and in several steps, is now superfluous to form a sliver. Afterwards, the slivers can be further combed with modern machines. An additional advantage is that the natural fibers can be fed directly from a scutching machine to a device according to the present invention, so that rolling up the natural fibers after scutching is unnecessary.

It will be apparent to one skilled in the art that the device can also be used to convert already rolled up scutched natural fibers into a sliver after unrolling.

According to a preferred embodiment, the transport device of the supply line comprises a conveyor belt. The conveyor belt forms the bearing surface configured to at least partially support the natural fibers in the layer of natural fibers.

According to one embodiment, a conveyor belt comprises a belt looped around a first roller at a first end and a second roller at a second end of the conveyor belt. The conveyor belt preferably comprises support rollers placed between the first roller at the first end and the second roller at the second end for supporting the belt. The belt is a solid belt of rubber, plastic or other suitable material. The belt is alternatively a chain conveyor of wood, metal, plastic or other suitable material. Another alternative is that the belt is formed by slats, the slats extending in a longitudinal direction. The said longitudinal direction of the slats is transverse to the supply direction A, for the conveyor belt of the supply line, and transverse to the sliver formation direction B, for the conveyor belt of the sliver forming line. The slats are made of wood, metal, plastic or another suitable material. Preferably, the belt of the conveyor belt of the supply line is a solid belt and the belt of the conveyor belt of the sliver forming line is formed by slats.

According to an alternative embodiment, the transport device of the supply line comprises transport belts. The transport belts are parallel to each other. The transport belts extend according to the supply direction A. Preferably, the transport device comprises at least two transport belts, more preferably at least three transport belts, even more preferably at least four transport belts and even more preferably at least five transport belts. The transport belts form the bearing surface configured to at least partially support the natural fibers in the layer of natural fibers. This embodiment is particularly advantageous in case the sliver is formed immediately after scutching, wherein, according to the prior art, natural fibers are discharged from the scutching line on outfeed transport belts. The outfeed transport belts of the scutching line can optionally be the transport device of the supply line, eliminating the need for a separate transport device and eliminating the need to transfer the natural fibers from the outfeed transport belts of the scutching line to the transport device of the supply line.

According to a preferred embodiment, the conveyor belt of the sliver forming line comprises combs for pulling out and entraining the natural fibers from the layer of natural fibers on the transport device of the supply line to the conveyor belt of the sliver forming line, to form a sliver. The combs extend from a surface formed by the conveyor belt of the sliver forming line.

The combs are advantageous in that the natural fibers are guaranteed to be pulled from the supply line onto the sliver forming line. An additional advantage is that the natural fibers are at least partially combed at the same time.

According to a preferred embodiment, the supply direction A and the sliver forming direction B form an angle Q of at least 90° and at most 180°.

An angle Q according to this embodiment is advantageous because it causes the natural fibers entrained on the conveyor belt of the sliver forming line to collide with the natural fibers in the layer of the natural fibers supplied on the transport device of the supply line, thus guaranteeing overlap between natural fibers that are entrained and natural fibers that are supplied and a continuous sliver of natural fibers is formed. Preferably, the angle Q is at least 110°, more preferably at least 125°, even more preferably at least 140° and even more preferably at least 155°. As a result, the natural fibers are entrained in a sliver forming direction B which is opposite to the supply direction A, thus positioning the natural fibers on the conveyor belt of the sliver forming line under the overhanging part of the natural fibers in the layer of natural fibers on the transport device of the supply line. This guarantees not only that the natural fibers form a continuous sliver, but also that the overhanging part of a natural fiber in the formed sliver is on top of an end of a natural fiber previously entrained by the sliver forming line and supported entirely by the conveyor belt of the sliver forming line. This is advantageous because when the formed sliver is entrained from e.g. the conveyor belt of the sliver forming line to another conveyor belt, the originally overhanging part of the natural fiber cannot sink between e.g. the conveyor belt of the sliver forming line and the other conveyor belt, whereby the formed sliver would be interrupted. Because the originally overhanging part of the natural fiber lies on top of an end of a natural fiber that was previously entrained by the sliver forming line, the originally overhanging part of the natural fiber will be entrained over a possible space between, for example, the conveyor belt of the sliver forming line and the other conveyor belt by the formed sliver.

According to an alternative embodiment, the supply direction A and the sliver forming direction B form an angle Q of at least 0° and at most 89°. This embodiment is advantageous, for example, in the event that a formed sliver is reversed by the sliver forming line. The overhanging part of a natural fiber in the formed sliver in this embodiment lies below an end of a natural fiber previously entrained by the sliver forming line and, upon reversal of the sliver, on top of the end of the natural fiber previously entrained by the sliver forming line. Reversing the sliver by the sliver forming line is advantageous for removal by gravity of the formed sliver from the conveyor belt of the sliver forming line. This is particularly advantageous in combination with a previously described embodiment wherein the conveyor belt of the sliver forming line comprises combs.

According to a preferred embodiment, the combs included in the conveyor belt of the sliver forming line are distributed in a regular manner over the conveyor belt of the sliver forming line. Preferably the teeth of the combs are aligned. This is advantageous for simple manufacture of the combs. The teeth of the combs are aligned at an angle to the sliver forming direction B. Preferably, the teeth of the combs are aligned transversely to the sliver formation direction B. This is particularly advantageous in case the belt of the conveyor belt of the sliver forming line is formed by slats. The teeth of a comb are preferably uniformly distributed over the comb. The teeth are preferably positioned transversely to the surface formed by the belt of the conveyor belt of the sliver forming line. This is advantageous for maximum engagement of the teeth in the natural fibers in the layer of natural fibers on the supply line.

According to a preferred embodiment, the conveyor belt of the sliver forming line comprises at least 400 and at most 5000 teeth of combs per m ² , preferably between 800 and 2500 teeth per m ² . This provides sufficient teeth for maximum engagement of the teeth in the natural fibers in the layer of natural fibers on the supply line, so that all the natural fibers are pulled from the layer of natural fibers on the supply line and placed on the conveyor belt of the sliver forming line. More teeth would mean that the fibers no longer sink between the teeth, which would reduce the grip on the natural fibres. The teeth are studs, needles, pins or other suitable means.

In one embodiment, the supply line comprises combs for combing the overhanging part of the natural fibers in the layer of natural fibers on the supply line. Preferably, the combs are placed next to the supply line. Preferably, the combs are rotatable combs. This is advantageous because as a result the natural fibers on the supply line are already at least partially separated and less entangled, so that the natural fibers can be pulled more easily and more evenly from the layer of natural fibers on the supply line.

According to a preferred embodiment, the device comprises a braking system for braking the natural fibers in the layer of natural fibers on the supply line. The braking system is positioned above the transport device of the supply line. The braking system extends along the supply direction A from in front of the sliver forming line to at least at the sliver forming line. The braking means is configured to brake the natural fibers in the layer of natural fibers on the conveyor belt of the supply line. Due to the braking means, natural fibers in the layer of natural fibers on the supply line experience a resistance, so that upon pulling out and entrainment of natural fibers from the layer of natural fibers on the supply line by the conveyor belt of the sliver forming line, it is prevented that neighboring natural fibers are also pulled out from the layer of natural fibers and are entangled, thus obtaining a formed sliver with irregular thickness or with interruptions. According to one embodiment, the braking means has an adjustable distance from the transport device of the supply line. The adjustable distance is at least 0 mm and at most 20 mm. The adjustable distance is measured as the smallest distance perpendicular from the bearing surface of the transport device of the supply line to the braking means. Alternatively, the braking means can be pressed against said bearing surface of the transport device of the supply line with a controllable pressure. This embodiment is advantageous for determining the degree of braking and resistance of the natural fibers on the supply line.

According to one embodiment, the braking means is a plate positioned above the conveyor belt of the supply line.

According to an alternative embodiment, the braking means is a conveyor belt, which is positioned above the transport device of the supply line.

According to one embodiment, a distance between the transport device of the supply line and the braking means near the conveyor belt of the sliver forming line is gradually greater. Said distance is defined as the smallest distance perpendicular from the bearing surface of the transport device of the supply line to the braking means. A gradually greater distance is advantageous for controlled and gradual release of natural fibers near the sliver forming line from the layer of natural fibers on the supply line.

According to one embodiment, the braking means comprises projections, such as studs, needles, pins or other suitable means, for better and controlled braking of the natural fibers on the supply line.

According to a preferred embodiment, the braking system comprises a clamping system, for clamping natural fibers on the transport device of the supply line, and an orientation system, for keeping natural fibers on the transport device of the supply line oriented.

The clamping system and the orientation system extend along the supply direction A. The orientation system extends further than the clamping system along the supply direction A. Preferably, the orientation system extends at least 1 cm beyond the clamping system, more preferably at least 5 cm, even more preferably at least 10 cm and even more preferably at least 15 cm. The clamping system is positioned at the said side edge of the transport device of the supply line intersecting the conveyor belt of the sliver forming line.

The clamping system comprises a conveyor belt or transport belt or conveyor chain which is positioned at a distance of at most 5 mm, preferably at most 4 mm, more preferably at most 3 mm and even more preferably at most 2 mm and even more preferably at most 1 mm from the transport device of the supply line. Said distance is defined as the smallest distance perpendicular from the bearing surface of the transport device of the supply line to the conveyor belt or the transport belt or the conveyor chain of the clamping system. The conveyor belt or the transport belt or the conveyor chain is preferably spring-loaded against the bearing surface of the transport device of the supply line. The conveyor belt or the transport belt or the conveyor chain has a width, viewed in the direction transverse to the supply direction A, of at most 20 cm, preferably at most 15 cm, more preferably at most 10 cm and even more preferably at most 5 cm. The conveyor belt or the transport belt or the conveyor chain of the clamping system is parallel to the transport device of the supply line. Parallel in this context means parallel to the bearing surface of the transport device.

The orientation system comprises a conveyor belt which is parallel to the transport device of the supply line. Parallel in this context means parallel to the bearing surface of the transport device. The conveyor belt of the orientation system is positioned next to the clamping system. The conveyor belt comprises a belt with a width, viewed in a direction transverse to the supply direction A, of at least 40 cm, preferably at least 50 cm, more preferably at least 60 cm, even more preferably at least 70 and even more preferably at least 80 cm. The conveyor belt of the orientation system is positioned at a distance of at least 0.5 mm and at most 3 mm, preferably at most 2.5 mm, more preferably at most 2.0 mm, even more preferably at most 1.5 mm and even more preferably at most 1.0 mm from the transport device of the supply line. Said distance is measured as the smallest distance perpendicular from the bearing surface of the transport device of the supply line to the conveyor belt of the orientation system.

This embodiment is advantageous because the clamping system ensures that the natural fibers on the supply line cannot be prematurely pulled out of the layer of natural fibers and entrained by the sliver forming line, while the orientation system provides a certain resistance, so that natural fibers adjacent to natural fibers entrained by the resistance of the orientation system remain oriented as well as possible transversely to the supply direction until the said neighboring fibers are also released by the clamping system. As a result, the formed sliver will be more continuous and uniform and the fibers will be oriented more in a direction parallel to the sliver forming direction B.

According to a preferred embodiment, the device comprises at least one pressing means for pressing the natural fibers against the conveyor belt of the sliver forming line. The pressing means is positioned a distance above the conveyor belt of the sliver forming line. The pressing means is placed near the first end of the conveyor belt of the sliver forming line. The pressing means is advantageous in pulling out and entraining the natural fibers by the conveyor belt of the sliver forming line to press free ends of the natural fibers against the conveyor belt of the sliver forming line, thereby more easily forming a sliver.

According to one embodiment, the pressing means comprises bars parallel to the belt of the conveyor belt of the sliver forming line and in a direction parallel to the sliver forming direction B. The bars are preferably curled near the first end of the conveyor belt of the sliver forming line away from the conveyor belt of the sliver forming line to form a funnel-shaped opening for the natural fibers between the bars and the conveyor belt of the sliver forming line. In combination with a previously described embodiment wherein the conveyor belt of the sliver forming line comprises combs, the bars are preferably positioned between the teeth of the combs.

According to a preferred embodiment, a pressing means is a rotatable cylindrical drum. The rotatable cylindrical drum is placed over at least a part of the conveyor belt, viewed in a direction transverse to the sliver forming direction. Preferably the cylindrical drum is freely movable and indirectly driven by contact with the natural fibers, or with the conveyor belt of the sliver forming line or with combs included in the conveyor belt of the sliver forming line. The cylindrical shell of the rotatable cylindrical drum is formed by spokes. In combination with a previously described embodiment wherein the conveyor belt of the sliver forming line comprises combs, the spokes are preferably positioned between the combs. Alternatively, the rotatable cylindrical drum is directly driven, for example by an electric motor.

According to one embodiment, the device comprises a plurality of pressing means, positioned at a distance above the conveyor belt of the sliver forming line and distributed between the first end and the second end of the conveyor belt of the sliver forming line. These pressing means can be placed at any place where it is advantageous to press the fibers against the conveyor belt of the sliver forming line.

According to one embodiment, the device comprises two rotatable and parallel sliver forming drums. The sliver forming drums are conically shaped at one end. The conically shaped end faces the first end of the transport device of the supply line. The sliver forming drums are preferably positioned in parallel. The sliver drums form an entry funnel for guiding the natural fibers from the supply line to the sliver forming line. The sliver forming drums are preferably driven. This embodiment is advantageous to avoid that a portion of the natural fibers in the layer of natural fibers on the supply line is insufficiently pulled out of the layer of natural fibers by the conveyor belt of the sliver forming line and help pull the natural fibers out of the layer of natural fibers.

According to a further embodiment, the sliver forming drums can be pressed against each other. Pressing is done by means of compressed air, hydraulic cylinders, a spring system, a counterweight or another suitable means. This embodiment is advantageous for pulling the natural fibers from the layer of natural fibers.

According to a preferred embodiment, along at least a portion of said side edge of the transport device of the supply line intersecting the conveyor belt of the sliver forming line, a guide profile is provided for guiding the natural fibers of the supply line to the sliver forming line and and for positioning the natural fibers at the correct location relative to the sliver forming line. The guide profile extends in a direction transverse to the bearing surface of the transport device of the supply line. The guide profile preferably extends lower than said bearing surface of the transport device of the supply line. This is advantageous to avoid the overhanging part of the natural fibers in the layer of natural fibers on the supply line becoming entangled in the transport device of the supply line, resulting in loss of and/or damage to the natural fibers and contamination and/or damage to the transport device of the supply line.

According to one embodiment, the device comprises a discharge line for discharging the formed sliver. The discharge line comprises a conveyor belt. A first end of the conveyor belt of the discharge line is placed at the second end of the conveyor belt of the sliver forming line. The conveyor belt of the discharge line is the same as in previously described embodiments of a conveyor belt for the supply line and the sliver forming line. Preferably, the conveyor belt of the discharge line is configured for a higher speed than the conveyor belt of the sliver forming line, thereby providing an additional combing action on the natural fibers of the formed sliver.

According to a further embodiment, at the second end of the conveyor belt of the discharge line, the device comprises a pair of rollers placed above and below the conveyor belt of the discharge line. These rollers are advantageous for carrying off the formed sliver from the conveyor belt of the discharge line to a storage medium, such as a jar, container, box or bale. Preferably, these rollers are configured for a higher speed than the conveyor belt of the discharge line, thereby providing an additional combing action on the natural fibers of the formed sliver.

According to one embodiment, the discharge line comprises pressing means for pressing the formed sliver against the conveyor belt of the discharge line. The pressing means are the same as the pressing means in previously described embodiments about the sliver forming line. Preferably, the pressing means are rotatable cylindrical drums. This embodiment is advantageous in order to prevent the formed sliver from sliding off the conveyor belt of the discharge line during discharge and/or being insufficiently entrained by the conveyor belt of the discharge line.

According to one embodiment, the conveyor belt of the sliver forming line is L- shaped. The conveyor belt of the sliver forming line comprises two legs. The conveyor belt comprises, in addition to the first roller at the first end and a second roller at the second end, at least a third roller, the third roller being positioned at the junction of the first leg and the second leg within the loop formed by the belt of the conveyor belt of the sliver forming line. The first leg is the length of the conveyor belt of the sliver forming line from the first roller to the third roller and the second leg is the length of the conveyor belt of the sliver forming line from the third roller to the second roller. The first leg extends in the sliver forming direction B. The L-shaped conveyor belt preferably comprises a pressing means, more preferably a rotatable cylindrical drum, in an inside corner formed by the first leg and the second leg, for pressing the formed sliver against the conveyor belt of the sliver forming line. The inside corner is preferably directed upwards. The pressing means is advantageous to avoid that when making the transition from the first leg to the second leg, the formed sliver becomes detached from the conveyor belt of the sliver forming line. This embodiment is particularly advantageous in combination with a previously described embodiment in which the device comprises a discharge line, the discharge line extending in a substantially different direction from the sliver forming direction B. The second leg serves as a transition from the sliver forming direction B to the direction in which the conveyor belt of the discharge line extends. This is particularly advantageous as a transition from a substantially vertical sliver forming direction B to a substantially horizontal direction in which the conveyor belt of the discharge line extends.

It will be apparent to one skilled in the art that a device according to the present invention can be used both off- and online, where online means that natural fibers are fed directly and preferably automatically from a scutching line to a device according to the present invention.

In a second aspect, the invention relates to a method for producing slivers with natural fibers, such as flax slivers.

In a preferred embodiment, the method comprises the steps of:

- supplying a layer of natural fibers on a transport device of a supply line along supply direction A, with the natural fibers oriented in a direction transverse to the supply direction A and with the transport device of the supply line extending from a first end along the supply direction A to a second end,

- entraining the natural fibers from the layer of natural fibers on a conveyor belt of a sliver forming line along a sliver forming direction B, with the conveyor belt of the sliver forming line extending from a first end along the sliver forming direction B to a second end.

The conveyor belt of the sliver forming line intersects a side edge of the transport device of the supply line between the first end and the second end of the transport device of the supply line. Said side edge extends along the supply direction A.

Natural fibers are provided in a layer with a thickness that is as uniform as possible on the conveyor belt of the supply line, the layer of natural fibers being partially supported by the conveyor belt of the supply line. The natural fibers are oriented in a direction transverse to the supply direction A. An overhanging part of the natural fibers in the layer of natural fibers is positioned on the side of the sliver forming line. Because the conveyor belt of the sliver forming line intersects a side edge of the transport device of the supply line, the overhanging part of the natural fibers at the level of the conveyor belt of the sliver forming line is entrained by the conveyor belt of the sliver forming line on the conveyor belt of the sliver forming line. The conveyor belt of the sliver forming line moves in a different direction and optionally faster than the conveyor belt of the supply line. Because the natural fibers on the sliver forming line move in a different direction and optionally faster than on the conveyor belt of the supply line, the natural fibers are pulled at an angle to the supply direction A from the layer of natural fibers of the transport device of the supply line in a direction parallel to the sliver forming direction B onto the conveyor belt of the sliver forming line and entrained and superimposed in a longitudinal direction of the natural fibers, whereby a sliver is formed.

This embodiment has the advantage, among other things, that a sliver of natural fibers can be formed immediately after scutching, without the natural fibers first having to be hackled in a hackling machine, in its traditional and outdated form, and it only then being possible for them to be formed into a sliver in several steps. An additional advantage of this method is that it is many times more efficient than a traditional method in which the natural fibers are rolled up after scutching, after which they have to be unrolled and hackled again before a sliver can be formed.

It will be apparent to one skilled in the art that a method according to the present invention can also be used to convert already rolled up scutched natural fibers into a sliver after unrolling.

According to a preferred embodiment, the natural fibers are pulled out of the layer of natural fibers at an angle Q with respect to the supply direction A of at least 20° and at most 180° in the sliver forming direction B. The angle Q is determined as the smallest angle between the positive sense of the supply direction A and the positive sense of the sliver forming direction B. This means that at an angle Q of 180° the directions A and B are opposite directions. An angle Q of at least 20° and at most 180° is suitable for automatically forming a sliver by pulling natural fibers from the layer of natural fibers on the supply line.

An angle Q of at least 90° and at most 180° is advantageous in a method according to the present embodiment because as a result the natural fibers entrained on the conveyor belt of the sliver forming line collide with the natural fibers in the layer of the natural fibers that are supplied on the conveyor belt of the supply line, thus guaranteeing overlap between natural fibers being discharged and natural fibers being supplied and a continuous sliver of natural fibers is formed. Preferably, the angle Q is at least 110°, more preferably at least 125°, even more preferably at least 140° and even more preferably at least 155°. As a result, the natural fibers are entrained in a sliver forming direction B which is opposite to the supply direction A, thus positioning the natural fibers on the conveyor belt of the sliver forming line under the overhanging part of the natural fibers in the layer of natural fibers on the transport device of the supply line. This is advantageous because when the formed sliver is entrained from e.g. the conveyor belt of the sliver forming line to another conveyor belt, the originally overhanging part of the natural fiber cannot sink between e.g. the conveyor belt of the sliver forming line and the other conveyor belt, whereby the formed sliver would be interrupted.

An angle Q of at least 20° and at most 89° is advantageous in a method according to the present embodiment in case a formed sliver is reversed by the sliver forming line. At an angle Q of at least 20° and at most 89°, the overhanging part of a natural fiber in the formed sliver lies below an end of a natural fiber previously entrained by the sliver forming line and, upon reversal of the sliver, on top of the end of the natural fiber previously entrained by the sliver forming line. Reversing the sliver by the sliver forming line is advantageous for removal by gravity of the formed sliver from the conveyor belt of the sliver forming line.

According to a preferred embodiment, upon entrainment on the sliver forming line, the natural fibers to form a sliver are pulled from the layer of natural fibers on the supply line by combs comprised in the conveyor belt of the sliver forming line. The combs extend from a surface formed by the conveyor belt of the sliver forming line. The combs are advantageous in that the natural fibers are guaranteed to be pulled from the supply line onto the sliver forming line. An additional advantage is that the natural fibers are at least partially combed at the same time.

According to a preferred embodiment, the natural fibers are braked on the supply line before entrainment on the sliver forming line. Due to the braking, natural fibers in the layer of natural fibers on the supply line experience a resistance, so that upon pulling out and entrainment of natural fibers from the layer of natural fibers on the supply line by the conveyor belt of the sliver forming line, it is prevented that neighboring natural fibers are also pulled out from the layer of natural fibers and are entangled, thus obtaining a formed sliver with irregular thickness or with interruptions. According to a further embodiment, the natural fibers are clamped on the transport device of the supply line at least as far as the sliver forming line during braking. The clamping of the natural fibers on the transport device of the supply line is advantageous in order to avoid natural fibers on the supply line from being pulled out prematurely by the conveyor belt of the sliver forming line, from the layer of natural fibers and entrained.

According to one embodiment, the natural fibers are guided between two rotating and parallel sliver forming drums to the conveyor belt of the sliver forming line before being entrained on the conveyor belt of the sliver forming line.

The sliver forming drums are conically shaped at one end. The conically shaped end faces the first end of the transport device of the supply line. The sliver forming drums are preferably positioned in parallel. The sliver drums form an entry funnel for guiding the natural fibers from the supply line to the sliver forming line. The sliver forming drums are preferably driven. This embodiment is advantageous to avoid that a portion of the natural fibers in the layer of natural fibers on the supply line is not pulled out of the layer of natural fibers by the conveyor belt of the sliver forming line and help pull the natural fibers out of the layer of natural fibers.

One skilled in the art will appreciate that a device according to the first aspect is preferably configured to perform a method according to the second aspect and that a method according to the second aspect is preferably carried out using a device according to the first aspect. Each feature described in this document, both above and below, can therefore relate to any of the three aspects of the present invention.

In a third aspect, the invention relates to a use of a device according to the first aspect or a method according to the second aspect for producing a sliver from flax or hemp.

This use results in an advantageous formation of a sliver from flax or hemp, because sliver formation can be carried out in an efficient manner immediately after scutching. This is particularly advantageous because much flax or hemp is grown in northern France, Belgium and the Netherlands, but is hackled and spun in low-wage countries. Due to the efficient formation of a sliver from flax or hemp, at least part of the processing of flax or hemp can be kept local, thus avoiding or reducing transport costs, and giving an important economic activity new opportunities in Europe. In what follows, the invention is described by way of non-limiting figures illustrating the invention, and which are not intended to and should not be interpreted as limiting the scope of the invention.

DETAI LED DESCRI PTI ON OF THE FI GURES

Figure 1 A, Figure 1 B, Figure 1 C and Figure 1 D show schematic plan views of mutual positions of the transport device of the supply line and the conveyor belt of the sliver forming line according to various embodiments of the present invention.

The supply line comprises a transport device (1) which extends from first end (3) along a supply direction (A) to a second end (4) The sliver forming line comprises a conveyor belt (2) extending from first end (5) along a sliver forming direction (B) to a second end (6).

The conveyor belt (2) of the sliver forming line intersects a side edge of the transport device (1) of the supply line between the first end (3) and the second end (4) of the transport device (1) of the supply line, wherein said side edge extends along the supply direction (A).

In Figures 1, said side edge is the bottom line of the transport device (1) of the supply line. In Figures 1A, 1C and ID, the conveyor belt (2) of the sliver forming line intersects said side edge with a side edge of the conveyor belt (2) of the sliver forming line extending transversely to the sliver forming direction (B). An intersection between said side edge with the side edge of the conveyor belt (2) transverse to the sliver forming direction (B) forms a gripping point (17) for the natural fibers of the supply line on the sliver forming line. In Figure IB, the conveyor belt (2) of the sliver forming line intersects said side edge with a side edge of the conveyor belt (2) of the sliver forming line extending along the sliver forming direction (B) and a side edge of the conveyor belt (2) falls transverse to the sliver forming direction (B) together with said side edge. In this case, the gripping point (17) is preferably at the center of the side edge of the conveyor belt (2) transverse to the sliver formation direction (B). In Figures IB and ID, the conveyor belt (2) of the sliver forming line passes under the transport device (1) of the supply line. The supply direction (A) and the sliver forming direction (B) form an angle (Q) of at least 20° and at most 180°. For clarity, an angle of 180° is also shown in Figures 1, which are opposite directions. In Figure 1A, the angle (Q) is an angle of 20°. The supply direction (A) and the sliver forming direction (B) have the same direction and sense. In Figure IB, the angle (Q) is an angle of 90°. The sliver forming line passes under the supply line. The supply direction (A) and the sliver forming direction (B) are transverse to each other. In Figure 1C, the angle (Q) is an angle of 160°. In this case, the natural fibers are entrained in a sliver forming direction (B) which is opposite to the supply direction (A), thus positioning the natural fibers on the conveyor belt (2) of the sliver forming line under the overhanging part of the natural fibers in the layer of natural fibers on the transport device (1) of the supply line. In Figure ID, the angle (Q) is also an angle of 160°. Once again the natural fibers are entrained in a sliver forming direction (B) which is opposite to the supply direction (A). The natural fibers are entrained by the conveyor belt (2) of the sliver forming line under the transport device (1) of the supply line.

Figure 2 shows a side view of a device according to an embodiment of the present invention.

The device comprises a supply line for a layer (8) of natural fibers. The supply line comprises a transport device (1). The transport device (1) comprises a conveyor belt. The transport device (1) of the supply line extends from a first end (3) along a supply direction (A) to a second end (4). The transport device (1) of the supply line comprises a bearing surface, the conveying belt, which is configured to at least partially, in a lying position, support and move the natural fibers in the layer (8) of natural fibers, wherein the natural fibers are oriented in a direction transverse to the supply direction (A).

The sliver forming line comprises a conveyor belt (2). The conveyor belt (2) of the sliver forming line extends from a first end (5) along a sliver forming direction (B) to a second end (6). The conveyor belt (2) of the sliver forming line is suitable for fully supporting the natural fibers, wherein the natural fibers are oriented in a direction parallel to the sliver forming direction (B). The conveyor belt (2) of the sliver forming line in this embodiment is an L-shaped conveyor belt. The conveyor belt (2) of the sliver forming line comprises combs (15), for pulling out and entraining the natural fibers from the layer (8) of natural fibers on the transport device (1) of the supply line, to the conveyor belt (2) of the sliver forming line, to form a sliver. The combs (15) extend from the conveyor belt (2) of the sliver forming line.

The conveyor belt (2) of the sliver forming line intersects a side edge of the transport device (1) of the supply line between the first end (3) and the second end (4) of the transport device (1) of the supply line. Said side edge extends along the supply direction (A).

Natural fibers are provided in a layer (8) with a thickness that is as uniform as possible on the transport device (1) of the supply line, the layer (8) of natural fibers being partially supported by the transport device (1) of the supply line. An overhanging part (7) of the natural fibers in the layer (8) of natural fibers is positioned on the side of the sliver forming line. Because the conveyor belt (2) intersects a side edge of the transport device (1) of the supply line between the first end (3) and the second end (4) of the transport device (1) of the supply line, the overhanging part (7) of the natural fibers at the level of the conveyor belt (2) of the sliver forming line are engaged by teeth of the combs (15) and are pulled by the combs (15) out of the layer (8) of natural fibers on the supply line and entrained on the conveyor belt (2) of the sliver forming line. Because the natural fibers on the conveyor belt (2) of the sliver forming line move in a different direction and optionally faster than on the transport device (1) of the supply line and because the teeth of the combs (15) initially engage only in the overhanging part (7) of the natural fibers, the natural fibers are carried in a direction at an angle to the supply direction (A) and parallel to the sliver forming direction (B) and superimposed in a longitudinal direction of the natural fibers, forming a sliver.

The device comprises a braking system (9) for braking the natural fibers in the layer (8) of natural fibers on the supply line. The braking system (9) comprises a clamping system (11) and an orientation system (10). The clamping system (11) and the orientation system (10) extend along the supply direction (A) up to the supply line. The orientation system (10) extends further than the clamping system (11) along the supply direction (A). The clamping system (11) comprises a transport belt positioned above the bearing surface of the transport device (1) of the supply line. The clamping system (11) is positioned at the said side edge of the transport device (1) of the supply line intersecting the conveyor belt (2) of the sliver forming line. The orientation system (10) is positioned next to the clamping system (11) above the transport device (1) of the supply line. The orientation system (10) comprises a conveyor belt which is positioned higher than the transport belt of the clamping system (11) above the transport device (1) of the supply line. In this embodiment, the conveyor belt of the orientation system (11) comprises projections for better and controlled braking of the natural fibers on the supply line.

The device according to the present embodiment comprises a discharge line for discharging the formed sliver. The discharge line comprises a conveyor belt (13). The conveyor belt (13) comprises projections for better entrainment of the formed sliver. A first end of the conveyor belt of the discharge line is placed at the second (6) end of the conveyor belt (2) of the sliver forming line. The conveyor belt (13) of the discharge line comprises at the second end a pair of rollers (14) positioned above and below the conveyor belt (13) of the discharge line for carrying off the formed sliver from the conveyor belt (13) of the discharge line to a storage means, such as a jar, container, box, or bale.

The device comprises pressing means for pressing the natural fibers against the conveyor belt (2) of the sliver forming line, as well as the formed sliver against the conveyor belt (13) of the discharge line. The pressing means are rotatable cylindrical drums (12) with a cylindrical shell formed by spokes. The rotatable cylindrical drum (12) at the first end (5) of the conveyor belt (2) of the sliver forming line has been omitted from Figures 2-5 for clarity.

Along at least a portion of said side edge of the transport device (1) of the supply line intersecting the conveyor belt (2) of the sliver forming line, a guide profile (16) is provided for guiding the natural fibers from the supply line to the sliver forming line. The guide profile (16) extends mainly in a direction transverse to the bearing surface of the transport device (1) of the supply line.

Figure 3 shows a front view of a device according to an embodiment of the present invention.

This embodiment is the same as the embodiment in Figure 2. Figure 3 clearly shows how the guide profile (16) prevents the overhanging part (7) of the natural fibers in the layer (8) of natural fibers from becoming entangled in the transport device (1) of the supply line and how the overhanging part (7) is guided to the conveyor belt (2) of the sliver forming line. Figure 4 shows a plan view of a device according to an embodiment of the present invention.

This embodiment is the same as the embodiment in Figure 2. Figure 4 clearly shows how the layer (8) of natural fibers is partially supported, in a lying position, on the transport device (1) of the supply line, with the natural fibers oriented in a direction transverse to the supply direction (A).

Figure 5 shows a perspective view of a device according to an embodiment of the present invention.

This embodiment is the same as the embodiment in Figure 2. The guide profile (16) prevents the overhanging part (7) of the natural fibers in the layer (8) of natural fibers from becoming entangled in the transport device (1) of the supply line and guides the overhanging part (7) to the conveyor belt (2) of the sliver forming line. The layer (8) of natural fibers is partially supported, in a lying position, on the transport device (1) of the supply line.